Cindy:
Thanks for coming to visit us here at the Moms Panel!
You've picked a very busy time of the year to go to Disney World, especially New Year's Eve. But you'll find that the crowds will dissipate near the end of your trip. When I KNOW crowds will be dense, like New Year's Eve, I typically recommend folks head to Epcot versus Magic Kingdom or Disney's Hollywood Studios. It is a much larger park and will accommodate many more guests than the smaller Magic Kingdom and DHS. Plus, it has vast more space for fireworks viewing. Additionally, many guests will head to the iconic MK by default, not realizing that the other parks celebrate big as well.
If you choose Epcot, don't make the mistake of arriving too late and finding the park closed due to capacity. Get there as early as you can and enjoy a slow pace in the park so you can celebrate come midnight. Enjoy the Kidscot Fun Stops at each pavilion in World Showcase; take the time to enjoy the interactive games at the end of Spaceship Earth that many casually walk by; check out both Innovention buildings and get the kids in on
Agent P's Showcase Adventure. There's lots to do with your kids to make the most of the day.
Wishing y'all a magical vacation!
Whitney